• Journal of radiological science and technology
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• v.41 no.5
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• pp.451-456
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• 2018

During last a decade, there has been increased demand for 3D-printed medical devices with significant improvement of 3D-Printer (also known as Additive. Manufacturing AM), which depend upon human body features. Especially, demand for personalized medical material is highly growing with being super-aged society. In this study, 3D-reconstructed 3D mesh image from CT/MRI-images is demonstrated to analyse each patients' personalized anatomical features by using in house, then to be able to manufacture its counterpart. Developed software is distributed free of charge, letting various researcher identify biological feature for each areas.

• Journal of Chest Surgery
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• v.32 no.8
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• pp.768-771
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• 1999

A 45 year old man was admitted for further examination of an abnormal shadow of the right posterior mediastinum. The patient suffered from dysesthesia in the right thoracic wall of dermatome T7. CT scan and MRI revealed that two separate tumors had developed in the right paravertebral area linked to the vertebral canal via an intervertebral foramina. One-stage removal of the tumors were performed safely through the right posterolateral thoracotomy following the resection of the rib head and vertebral pedicle. The tumors were confirmed as histologically neurilemomas. The postoperative course was uneventful.

• Journal of the Korean Institute of Telematics and Electronics
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• v.18 no.2
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• pp.54-63
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• 1981

An ultrasonic imaging system with fan reflection mode time of fight is developed and its performance has been examined by system implementation. Experimental results obtained indicafe potential of the method for tomographic imaging. The basic concept of this method is reconstruction of reflectivity with reflection data collected in fan mode using a new "arbitrary ray" reconstruction algorithm. Computer simulations as well as experimental results are presented.presented.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.7
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• pp.834-850
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• 2011

In this paper, a novel tissue engineering scaffold design method based on triply periodic minimal surface (TPMS) is proposed. After generating the hexahedral elements for a 3D anatomical shape using the distance field algorithm, the unit cell libraries composed of triply periodic minimal surfaces are mapped into the subdivided hexahedral elements using the shape function widely used in the finite element method. In addition, a heterogeneous implicit solid representation method is introduced to design a 3D (Three-dimensional) bio-mimetic scaffold for tissue engineering from a sequence of computed tomography (CT) medical image data. CT image of a human spine bone is used as the case study for designing a 3D bio-mimetic scaffold model from CT image data.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.4
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• pp.1714-1720
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• 2012

The purpose of the study was to evaluation of the radiation dose reduction and the possibility of the maintainability of the adequate image quality using various automatic exposure control (AEC) systems in multi-detector computed tomography (MDCT). We used three AEC systems for the study: General Electric Healthcare (Auto-mA 3D), Philips Medical systems (DoseRight) and Siemens Medical Solutions (Care Dose 4D). The general scanning protocol was created for the each examination with the same scanning parameters as many as possible. In the various AEC systems, the evaluation of reduced-dose was evaluated by comparing to fixed mAs with using human phantom. The image quality of the phantom was evaluated with measuring the image noise (standard deviation) by insert regions of interests. Finally, when we applied to AEC for three manufacturers, the radiation dose reduction decreased each 35.3% in the Auto-mA 3D, 58.2% in the DoseRight, and 48.6% in the Care Dose 4D. And, there was not statistical significant difference among the image quality in the Strong/Weak of the Care Dose 4D(P=.269). This applies to variety of the AEC systems which will be very useful to reduce the dose and to maintain the high quality.

• Progress in Medical Physics
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• v.25 no.4
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• pp.271-280
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• 2014

Recently, digital breast tomosynthesis (DBT) has been investigated to overcome the limitation of conventional mammography for overlapping anatomical structures and high patient dose with cone-beam computed tomography (CBCT). However incomplete sampling due to limited angle leads to interference on the neighboring slices. Many studies have investigated to reduce artifacts such as interference. Moreover, appropriate filters for tomosynthesis have been researched to solve artifacts resulted from incomplete sampling. The primary purpose of this study is finding appropriate filter scheme with FBP reconstruction for DBT system to reduce artifacts. In this study, we investigated characteristics of various filter schemes with simulation and prototype digital breast tomosynthesis under same acquisition parameters and conditions. We evaluated artifacts and noise with profiles and COV (coefficinet of variation) to study characteristic of filter. As a result, the noise with parameter 0.25 of Spectral filter reduced by 10% in comparison to that with only Ramp-lak filter. Because unbalance of information reduced with decreasing B of Slice thickness filter, artifacts caused by incomplete sampling reduced. In conclusion, we confirmed basic characteristics of filter operations and improvement of image quality by appropriate filter scheme. The results of this study can be utilized as base in research and development of DBT system by providing information that is about noise and artifacts depend on various filter schemes.

• Journal of the Korean Society of Radiology
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• v.82 no.1
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• pp.219-224
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• 2021

Leiomyosarcoma (LMS) is a soft tissue sarcoma that originates from smooth muscle cells. It is commonly found in the uterus but can occur throughout the body, including the retroperitoneal space, abdominal cavity, and any vascular structure. Although there are many case reports of uterine or vascular LMS metastasizing to the heart, cardiac metastasis from nonvisceral lesions has only been reported in two cases. Herein we report a rare case of a patient presenting metastatic LMS from the left flank in the right ventricle observed with echocardiography and enhanced computed tomography.

• Journal of the Korean Society of Radiology
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• v.83 no.4
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• pp.904-909
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• 2022

Uterine cervical cancer is one of the most common malignancies of the female genital tract. Most recurrent cases of uterine cervical cancer are diagnosed within two years after primary treatment, and late recurrence after a disease-free interval of more than five years is rare. In addition, peritoneal metastases usually present as multifocal discrete nodules in the peritoneal cavity with nodular or diffuse peritoneal thickening. Herein, we report an extremely rare case of late recurrent cervical cancer peritoneal metastasis with an unusual manifestation of a large, solitary necrotic mass in the right subphrenic space on contrast-enhanced CT.

• The Journal of Korean Academy of Prosthodontics
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• v.57 no.3
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• pp.219-224
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• 2019

Purpose: The image registration of radiographic image and digital surface data is essential in the computer-guided implant guide system. The purpose of this study was to examine the effects of using micro-screw on the working time and convenience of operators in the process of image matching for guided implant surgery. Materials and methods: A mandibular dental model was prepared in partial edentulism for Kennedy class I classification. Two micro-screws were placed on the each side of retromolar area. Radiographic and scan images were taken using computed-tomography and digital scanning. The images were superimposed by 12 operators in software in two different conditions: using remaining teeth image alone and using teeth and micro-screws images. Working time, operator convenience and satisfaction were obtained, and analyzed using the Mann-Whitney U test (${\alpha}=.05$). Results: The working time was not statistically different between image registration conditions (P>.05); however, operator convenience and satisfaction were higher in the teeth and micro-screw assisted condition than in the teeth-alone assisted condition (P<.001). Conclusion: The use of micro-screw for the image registration has no effect in working time reduction, but improves operator convenience and satisfaction.

• Journal of the Korean Society of Radiology
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• v.83 no.4
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• pp.808-829
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• 2022

Hepatocellular carcinoma (HCC) can be diagnosed noninvasively on multiphasic CT and MRI based on its distinctive imaging findings. These features include arterial phase hyperenhancement and washout on portal or delayed phase images. However, radiologists face significant diagnostic challenges because some HCCs exhibit atypical imaging characteristics. In addition to many HCC-mimicking lesions, such as arterioportal shunts, combined HCC-cholangiocarcinoma, intrahepatic cholangiocarcinoma, and hemangioma present a challenge for radiologists in actual clinical practice. The ability to distinguish HCCs from mimickers on initial imaging examinations is crucial for appropriate management and treatment decisions. Therefore, this pictorial review presents the imaging findings of atypical HCCs and HCCs mimicking malignant and benign lesions and discusses important clues that may help narrow down the differential diagnosis.